(a) Field of the invention
The present invention relates to a low magnification microscope objective and, more specifically, to an objective of achromat designed for magnification x4 and N.A. 0.1.
(b) Description of the prior art
An objective of achromat for magnification on the order of x4, there have hitherto been offered lens systems consisting of two components of four elements including ones having small radii of curvature on the lens surfaces. Lenses having such small radii of curvature on their surfaces cannot be manufactured with high productivity since it is impossible to arrange a large number of such lenses on a grinding support at a time. Further, the aforementioned objective consisting of two components of four lens elements were not satisfactory in that they permitted microscopic observation of flat image only within narrow ranges.